There are several ways to knurl a bullet.
This is with 2 files.
http://www.youtube.com/watch?v=NncCcscSQa8
This is with a Corbin knurling tool which is expensive.
http://www.corbins.com/hct-2.htm
You can also just add a few cannelures with this tool.
http://www.ch4d.com/?com=catalog&vie...ct&alias=12000